Adding and Subtracting Matrices

Matrix operations:
What must be true in order to ADD two matrices?

• They must be square.

• The dimensions must be equal.

• The determinant can't equal 0.

• The column of the 1st must equal the row of the 2nd.

A+B=?

• 
• 
• 
• 
• You can't add them because they don't have the same dimensions.

• A

• B

• C

• D

• A

• B

• C

• D

In Matrix R (pictured) what element is in the second row, third column?

• 8

• 9.01

• 6

• 1

Add.

• -2   4   -9
  -1   -6   -17

• -8   12   -9
  1   6   17

• -8   4   -9
  15   6   7

• -2   -4   -9
  15   6    7

Solve for matrix X.

• -9

  5

  3

• 9

  13

  -9

• 15

  -5

  3

• 10

  4

  6

Solve for matrix Y.

• -4    9
  -11    9

• 4   -8
  11   8

• 4   -9
  11   9

• -4   9
  11   -9

• A

• B

• C

• D

• A

• B

• C

• D